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Selected AbstractsImpact of an extreme melt event on the runoff and hydrology of a high Arctic glacierHYDROLOGICAL PROCESSES, Issue 6 2003Sarah Boon Abstract On 28,30 July 2000, an extreme melt event was observed at John Evans Glacier (JEG), Ellesmere Island (79° 40,N, 74° 00,W). Hourly melt rates during this event fell in the upper 4% of the distribution of melt rates observed at the site during the period 1996,2000. Synoptic conditions during the event resulted in strong east-to-west flow over the northern sector of the Greenland Ice Sheet, with descending flow on the northwest side reaching Ellesmere Island. On JEG, wind speeds during the event averaged 8·1 m s,1 at 1183 m a.s.l., with hourly mean wind speeds peaking at 11·6 m s,1. Air temperatures reached 8°C, and rates of surface lowering measured by an ultrasonic depth gauge averaged 56 mm day,1. Calculations with an energy balance model suggest that increased turbulent fluxes contributed to melt enhancement at all elevations on the glacier, while snow albedo feedback resulted in increased melting due to net radiation at higher elevations. The event was responsible for 30% of total summer melt at 1183 m a.s.l. and 15% at 850 m a.s.l. Conditions similar to those during the event occurred on only 0·1% of days in the period 1948,2000, but 61% of events occurred in the summer months and there was an apparent clustering of events in the 1950s and 1980s. Such events have the potential to impact significantly on runoff, mass balance and drainage system development at high Arctic glaciers, and changes in their incidence could play a role in determining how high Arctic glaciers respond to climate change and variability. Copyright © 2003 John Wiley & Sons, Ltd. [source] Reduction-Sensitive Self-Aggregates as a Novel Delivery SystemMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 8 2010Ju Eun Kim Abstract Methoxy PEG amine with molecular weight of 5k and , -caprolactone with molecular weight of 1,960 were conjugated to a peptide comprising three cysteine residues. The shift of peak molecular weight and narrow molecular weight distribution in GPC trace without any noticeable shoulder as well as 1H NMR analysis confirmed the successful synthesis of the copolymer. A modified O/W dialysis system was employed to prepare self-aggregates having the size around 210,nm. During the dialysis, stabilized aggregates were obtained by intermolecular disulfide bonds via oxidation. Critical aggregate concentration (CAC) of the copolymer was determined as 0.07,mg,·,mL,1 and disulfide-stabilized self-aggregates remained stable regardless of the concentration without displaying CAC. Doxorubicin-loading amount and efficiency was 8.7 and 26.0%, respectively. Release profile of doxorubicin below CAC at 37,°C showed a sustained release and the addition of D,L -dithiothreitol (DTT) after 24,h triggered a burst release of doxorubicin. Intermolecular disulfide bonds via oxidation stabilized the polymeric aggregates even in the diluted condition similar to that in the bloodstream and addition of DTT destabilized the aggregates to burst encapsulated doxorubicin in the reductive condition. [source] Occupational exposure to methyl tertiary butyl ether in relation to key health symptom prevalence: the effect of measurement error correctionENVIRONMETRICS, Issue 6 2003Aparna P. Keshaviah Abstract In 1995, White et al. reported that methyl tertiary butyl ether (MTBE), an oxygenate added to gasoline, was significantly associated with key health symptoms, including headaches, eye irritation, and burning of the nose and throat, among 44 people occupationally exposed to the compound and for whom serum MTBE measurements were available (odds ratio (OR),=,8.9, 95% CI,=,[1.2, 75.6]). However, these serum MTBE measurements were available for only 29 per cent of the 150 subjects enrolled. Around the same time, Mannino et al. conducted a similar study among individuals occupationally exposed to low levels of MTBE and did not find a significant association between exposure to MTBE and the presence of one or more key health symptoms among the 264 study participants (OR,=,0.60, 95% CI,=,[0.3, 1.21]). In this article, we evaluate the effect of MTBE on the prevalence of key health symptoms by applying a regression calibration method to White et al.'s and Mannino et al.'s data. Unlike White et al., who classified exposure using actual MTBE levels among a subset of the participants, and Mannino et al., who classified exposure based on job category among all participants, we use all of the available data to obtain an estimate of the effect of MTBE in units of serum concentration, adjusted for measurement error due to using job category instead of measured exposure. After adjusting for age, gender and smoking status, MTBE exposure was found to be significantly associated with a 50 per cent increase in the prevalence of one or more key health symptoms per order of magnitude increase in blood concentration on the log10 scale, using data from the 409 study participants with complete information on the covariates (95% CI,=,[1.00, 2.25]). Simulation results indicated that under conditions similar to those observed in these data, the estimator is unbiased and has a coverage probability close to the nominal value. The methodology illustrated in this article is advantageous because all of the available data were used in the analysis, obtaining a more precise estimate of exposure effect on health outcome, and the estimate is adjusted for measurement error due to using job category instead of measured exposure. Copyright © 2003 John Wiley & Sons, Ltd. [source] Occurrence, ecology and potential impact of the New Zealand wheat bug Nysius huttoni White (Hemiptera: Lygaeidae) in BelgiumEPPO BULLETIN, Issue 2 2010J. Bonte In 2002 the New Zealand wheat bug Nysius huttoni White was observed for the first time in the Netherlands and Belgium. The introduction of N. huttoni to these regions presumably occurred via overseas transport of apple and kiwi fruits from New Zealand. Laboratory experiments showed that both eggs and adults of N. huttoni were capable of surviving cold conditions similar to those in overseas transportation. Specimens were sampled in Belgium and the Netherlands, and a DNA sequence analysis indicated a 100% similarity with N. huttoni material collected in Christchurch, New Zealand. The distribution of the lygaeid in Belgium in 2008 was studied based on a systematic sampling at 105 locations. The bug had been able to spread over most of the Belgian territory, with the exception of the most southern and eastern provinces. Given the poor flight capacity of Belgian N. huttoni populations, other methods of dispersal may be involved. N. huttoni occurred primarily in ruderal habitats, and its weedy host plants belong to very common plant families. Several observations support N. huttoni not being a threat for agricultural crops in Belgium under the present conditions of climate and soil usage. [source] Activation of PPAR-, and PTEN cascade participates in lovastatin-mediated accelerated differentiation of oligodendrocyte progenitor cellsGLIA, Issue 14 2010Ajaib S. Paintlia Abstract Previously, we and others documented that statins including-lovastatin (LOV) promote the differentiation of oligodendrocyte progenitor cells (OPCs) and remyelination in experimental autoimmune encephalomyelitis (EAE), an multiple sclerosis (MS) model. Conversely, some recent studies demonstrated that statins negatively influence oligodendrocyte (OL) differentiation in vitro and remyelination in a cuprizone-CNS demyelinating model. Therefore, herein, we first investigated the cause of impaired differentiation of OLs by statins in vitro settings. Our observations indicated that the depletion of cholesterol was detrimental to LOV treated OPCs under cholesterol/serum-deprived culture conditions similar to that were used in conflicting studies. However, the depletion of geranylgeranyl-pp under normal cholesterol homeostasis conditions enhanced the phenotypic commitment and differentiation of LOV-treated OPCs ascribed to inhibition of RhoA-Rho kinase. Interestingly, this effect of LOV was associated with increased activation and expression of both PPAR-, and PTEN in OPCs as confirmed by various pharmacological and molecular based approaches. Furthermore, PTEN was involved in an inhibition of OPCs proliferation via PI3K-Akt inhibition and induction of cell cycle arrest at G1 phase, but without affecting their cell survival. These effects of LOV on OPCs in vitro were absent in the CNS of normal rats chronically treated with LOV concentrations used in EAE indicating that PPAR-, induction in normal brain may be tightly regulated-providing evidences that statins are therapeutically safe for humans. Collectively, these data provide initial evidence that statin-mediated activation of the PPAR-,-PTEN cascade participates in OL differentiation, thus suggesting new therapeutic-interventions for MS or related CNS-demyelinating diseases. © 2010 Wiley-Liss, Inc. [source] Effect of seed coating on plant growth and soil conditions: A preliminary study for restoration of degraded rangeland in the Qinghai,Tibetan Plateau, ChinaGRASSLAND SCIENCE, Issue 3 2010Yingchun Liu Abstract Rangeland degradation is a significant problem in the Qinghai,Tibetan Plateau, China. Restoration of the degraded rangelands through reseeding is being undermined by poor seedling growth under adverse soil moisture and nutrition conditions. Accordingly, seeds of Italian ryegrass (Lolium multiflorum) and Chinese milk vetch (Astragalus sinicus) were coated with a mixture of hygroscopic and plant-derived polysaccharide gums and alga powder (Phaeocystis sp. necolon-1), and inoculated with spores of microorganisms (Aspergillus sp. and Streptomyces sp.), serving as coating mixture decomposers, in order to improve rhizosphere moisture and nutrition. In a growth chamber simulating spring climate on the Plateau, seedling emergence of the coated seeds was 60,80 and 48,82%, respectively, for the two plant species in comparison to 38 and 24% for the uncoated seeds, which was due to moisture being supplied by the coat. In the outdoor pots with soil texture and moisture conditions similar to those of the degraded rangelands on the Plateau, dry weight of the plants from the coated seeds was 109,184 and 118,156 mg plant,1 for the respective plant species, while that of the plants from uncoated seeds was 18,20 and 10,11 mg plant,1. The number of Rhizobium sp. nodules on Chinese milk vetch plants from the coated seeds was 21,25 plant,1 while 0,2 in plants from uncoated seeds. Enhancement of plant growth was caused by increased activity of soil microbes. Plant growth on the soil after sampling plants from the coated seeds was also enhanced, indicating sustainability of improvement of soil conditions. Thus seed coating with hygroscopic nutrient-source materials and inoculation with microorganism spores as slow decomposers of the coating materials is a promising method for restoring degraded rangelands. [source] Two-dimensional psychophysics in chickens and humans: Comparative aspects of perceptual relativityJAPANESE PSYCHOLOGICAL RESEARCH, Issue 4 2008PETRA HAUF Abstract:, Whereas the contextual basis of psychophysical responding is well founded, the compound influence of sensory and perceptual frames of reference constitutes a challenging issue in comparative one- and multidimensional psychophysics (e.g., Sarris, 2004, 2006). We refer to previous investigations, which tested the assumption that the chicken's relational choice in the one-dimensional case is systematically altered by context conditions similar to the findings stemming from human participants. In this paper mainly the context-dependent stimulus coding was investigated for the important, but largely neglected, two-dimensional case in humans and chickens. Three strategies were predicted for the generalization of size discriminations, which had been learned in a different color context. In two experiments, which varied in the testing procedure, both species demonstrated profound contextual effects in psychophysics; they differed, however, in the way the information from either dimension was used: Chickens throughout used color as a cue to separate the respective size discriminations and generalizations. Whereas humans predominantly generalized according to size information only or according to absolute stimulus properties, the chickens showed some important species-specific differences. Common and heterogeneous findings of this line of comparative research in multidimensional psychophysics are presented and discussed in various ways. [source] Detecting local adaptation in widespread grassland species , the importance of scale and local plant communityJOURNAL OF ECOLOGY, Issue 6 2006ARMIN BISCHOFF Summary 1Adaptation of plant populations to local environments has been shown in many species but local adaptation is not always apparent and spatial scales of differentiation are not well known. In a reciprocal transplant experiment we tested whether: (i) three widespread grassland species are locally adapted at a European scale; (ii) detection of local adaptation depends on competition with the local plant community; and (iii) local differentiation between neighbouring populations from contrasting habitats can be stronger than differentiation at a European scale. 2Seeds of Holcus lanatus, Lotus corniculatus and Plantago lanceolata from a Swiss, Czech and UK population were sown in a reciprocal transplant experiment at fields that exhibit environmental conditions similar to the source sites. Seedling emergence, survival, growth and reproduction were recorded for two consecutive years. 3The effect of competition was tested by comparing individuals in weeded monocultures with plants sown together with species from the local grassland community. To compare large-scale vs. small-scale differentiation, a neighbouring population from a contrasting habitat (wet-dry contrast) was compared with the ,home' and ,foreign' populations. 4In P. lanceolata and H. lanatus, a significant home-site advantage was detected in fitness-related traits, thus indicating local adaptation. In L. corniculatus, an overall superiority of one provenance was found. 5The detection of local adaptation depended on competition with the local plant community. In the absence of competition the home-site advantage was underestimated in P. lanceolata and overestimated in H. lanatus. 6A significant population differentiation between contrasting local habitats was found. In some traits, this small-scale was greater than large-scale differentiation between countries. 7Our results indicate that local adaptation in real plant communities cannot necessarily be predicted from plants grown in weeded monocultures and that tests on the relationship between fitness and geographical distance have to account for habitat-dependent small-scale differentiation. Considering the strong small-scale differentiation, a local provenance from a different habitat may not be the best choice in ecological restoration if distant populations from a more similar habitat are available. [source] Dysplasia and carcinoma development in a repeated dextran sulfate sodium-induced colitis modelJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2002Isao Okayasu Abstract Background: As an important mechanism underlying the increased risk of colorectal carcinoma development in patients with long-standing ulcerative colitis, promotion as a result of the regenerative process has been proposed. In the present study, a dysplasia-carcinoma sequence in a novel repeated colitis model in mice is documented. Methods: Repeated colitis was induced by nine administration cycles of 3% dextran sulfate sodium (DSS; molecular weight, 54 000): each administration cycle comprised 3% DSS for 7 days followed by distilled water for the subsequent 14 days, to give conditions similar to the clinically observed active and remission phases in humans. Results: Multiple colorectal tumors (nine low- and four high-grade dysplasias and two carcinomas) developed in 25 mice. These neoplastic lesions consisted of tubular structures, presenting as various types of elevated, flat and depressed tumor, similar to those in ulcerative colitis patients. A time-course study with assessment of the severity of colitis and in vivo bromodeoxyuridine uptake during a single 3% DSS administration cycle revealed a high level of regenerative activity in the colitis-affected mucosal epithelia. Conclusion: Thus, with the present repeated colitis model, regeneration and neoplastic lesions were apparent, the biological features of which provide evidence of a colorectal dysplasia,invasive carcinoma sequence in ulcerative colitis. [source] Late Quaternary deglaciation and climate history of the Larsemann Hills (East Antarctica)JOURNAL OF QUATERNARY SCIENCE, Issue 4 2004Elie Verleyen Abstract The Late Quaternary climate history of the Larsemann Hills has been reconstructed using siliceous microfossils (diatoms, chrysophytes and silicoflagellates) in sediment cores extracted from three isolation lakes. Results show that the western peninsula, Stornes, and offshore islands were ice-covered between 30,000,yr,BP and 13,500,cal.,yr,BP. From 13,500,cal.,yr,BP (shortly after the Antarctic Cold Reversal) the coastal lakes of the Larsemann Hills were deglaciated and biogenic sedimentation commenced. Between 13,500 and 11,500,cal.,yr,BP conditions were warmer and wetter than during the preceding glacial period, but still colder than today. From 11,500 to 9500,cal.,yr,BP there is evidence for wet and warm conditions, which probably is related to the early Holocene climate optimum, recorded in Antarctic ice cores. Between 9500 and 7400,cal.,yr,BP dry and cold conditions are inferred from high lake-water salinities, and low water levels and an extended duration of nearshore sea-ice. A second climate optimum occurred between 7400 and 5230,cal.,yr,BP when stratified, open water conditions during spring and summer characterised the marine coast of Prydz Bay. From 5230 until 2750,cal.,yr,BP sea-ice duration in Prydz Bay increased, with conditions similar to the present day. A short return to stratified, open water conditions and a reduction in nearshore winter sea-ice extent is evident between 2750 and 2200,cal.,yr,BP. Simultaneously, reconstructions of lake water depth and salinity suggests relatively humid and warm conditions on land between 3000 and 2000,cal.,yr,BP, which corresponds to a Holocene Hypsithermal reported elsewhere in Antarctica. Finally, dry conditions are recorded around 2000, between 760 and 690, and between 280 and 140,cal.,yr,BP. These data are consistent with ice-core records from Antarctica and support the hypothesis that lacustrine and marine sediments on land can be used to evaluate the effect of long-term climate change on the terrestrial environment. Copyright © 2004 John Wiley & Sons, Ltd. [source] Enhanced Mechanical Performance of Self-Bundled Electrospun Fiber Yarns via Post-TreatmentsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 10 2008Xuefen Wang Abstract A new route to high-performance electrospun polymer fibers was developed using a self-bundling electrospinning technique combined with post-treatments such as stretching and annealing under conditions similar to those used for conventional fibers. Self-bundled electrospun PAN fiber yarns were characterized by SEM, mechanical tests, polarized FT-IR spectroscopy and WAXD. The obtained results revealed that the PAN nanofiber yarns possessed enhanced alignment, a higher degree of crystallinity and higher molecular orientation after treatments, resulting in a remarkable improvement in mechanical performance, approaching the strength value of the corresponding conventional fibers. [source] Effect of Pepino mosaic virus on the yield and quality of glasshouse-grown tomatoes in the UKPLANT PATHOLOGY, Issue 5 2006N. J. Spence Two fully replicated trials were conducted with glasshouse-grown tomatoes, under conditions similar to commercial production, to define the impact of Pepino mosaic virus (PepMV). PepMV was not found to reduce bulk yields in these trials, but the quality of tomato fruits harvested was reduced significantly. Compared with uninoculated, PepMV-free control plants, 6·5% of fruits of PepMV-affected cv. Espero were downgraded from class 1 in trial 1. In trial 2, an average 38% of class 1 fruits from PepMV-affected cvs Espero and Encore were lost as a result of downgrading. Loss of quality was mainly a result of blotchy ripening, gold marbling, gold spot, and symptoms directly attributed to PepMV infection. PepMV infection also affected fruit size. The results are discussed in relation to the demands of multiple retailers in the UK for class 1 tomatoes only. [source] Activation of human T lymphocytes under conditions similar to those that occur during exposure to microgravity: A proteomics studyPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 7 2005Angela Risso Abstract A number of experiments, conducted under microgravity conditions, i.e. in space shuttle biolaboratories or in ground based systems simulating the conditions occurring in microgravity, show that in hypogravity, in vitro human lymphocyte activation is severely impaired. However, very early stimulation steps of T lymphocytes are not compromised, since CD69 receptor, the earliest membrane activation marker, is expressed by T cells at a level comparable to that observed on 1 g activated lymphocytes. Since CD69 engagement, together with submitogenic doses of phorbol esters, transduces an activation signal to T lymphocytes, we undertook a comparative study on the stimulation mediated through this receptor on human CD3+ cells cultured under conditions similar to those which occur during exposure to microgravity, i.e. in clinorotation, or at 1 g. During the early hours of activation, increased levels of intracellular calcium and increased mitochondrial membrane potential were detectable in clinorotating as well as in 1 g cells. However, after 48 hours clinorotation, interleukin 2 production by T lymphocytes was significantly reduced and cell proliferation was greatly decreased. By means of a differential proteomics approach on T cells activated in clinorotation or at 1 g for 48 hours, we were able to detect statistically significant quantitative protein alterations. Seven proteins with modified expression values were identified; they are involved in nucleic acids processing, proteasome regulation and cytoskeleton structure. [source] Dental implants: Maintenance, care and treatment of peri-implant infectionAUSTRALIAN DENTAL JOURNAL, Issue 4 2003S. Chen Abstract Osseointegration is becoming increasingly routine in the rehabilitation of partially or fully edentulous patients. However, the surrounding tissues may be subject to inflammatory conditions similar to periodontal disease and so require maintenance. This article discusses the background, aetiology, diagnosis of peri-implant diseases, and the maintenance, care and treatment of peri-implant infection in osseointegrated implants. Three case studies are presented to illustrate points in the care of implants. [source] Investigating the potential of Bacillus subtilis ,-amylase as a pressure-temperature-time indicator for high hydrostatic pressure pasteurization processesBIOTECHNOLOGY PROGRESS, Issue 4 2009Tara Grauwet Abstract The potential of Bacillus subtilis ,-amylase (BSA) as a pressure-temperature-time indicator (pTTI) for high pressure pasteurization processing (400,600 MPa; Ti 10,40°C; 1,15 min) was investigated. A stepwise approach was followed for the development of an enzyme-based, extrinsic, isolated pTTI. First, based on literature data on the pressure stability, BSA was selected as a candidate indicator. Next to the accuracy and ease of the measurement of the indicator's response (residual activity) to the pressure treatment, the storage and handling stability of BSA at atmospheric pressure was verified. Second, the stability of BSA at a constant temperature (T) and time in function of pressure (p) was investigated. Solvent engineering was used to shift the inactivation window of BSA in the processing range of interest. Third, the enzyme (1 g/L BSA,MES 0.05 M pH 5.0) was kinetically calibrated under isobaric-isothermal conditions. Time dependent changes in activity could be modeled best by a first-order model. Except for low pressures and high temperatures, a synergistic effect between pressure and temperature could be observed. Based on the model selected to describe the combined p,T-dependency of the inactivation rate constant, an elliptically shaped isorate contour plot could be constructed, illustrating the processing range where BSA can be used to demonstrate temperature gradients. Fourth, the validity of the kinetic model was tested successfully under dynamic conditions similar to those used in food industry. Finally, the indicator was found suitable to demonstrate nonuniformity in two-sectional planes of a vertical, single vessel system. © 2009 American Institute of Chemical Engineers. Biotechnol. Prog., 2009 [source] Lamotrigine versus lithium as maintenance treatment in bipolar I disorder: an open, randomized effectiveness study mimicking clinical practice.BIPOLAR DISORDERS, Issue 5 2010The 6th trial of the Danish University Antidepressant Group (DUAG-6) Licht RW, Nielsen JN, Gram LF, Vestergaard P, Bendz H. Lamotrigine versus lithium as maintenance treatment in bipolar I disorder: an open, randomized effectiveness study mimicking clinical practice. The 6th trial of the Danish University Antidepressant Group (DUAG-6). Bipolar Disord 2010: 12: 483,493. © 2010 The Authors. Journal compilation © 2010 John Wiley & Sons A/S. Objectives:, In industry-generated pivotal studies, lamotrigine has been found to be superior to placebo and comparable to lithium in the maintenance treatment of bipolar I disorder. Here, we directly compared lamotrigine to lithium under conditions similar to clinical routine conditions. Methods:, Adult bipolar I disorder patients with at least two episodes within the last five years and an index episode requiring treatment were randomized to lithium (n = 78; doses adjusted to obtain serum levels of 0.5,1.0 mmol/L) or to lamotrigine (n = 77; up-titrated to 400 mg/day) as maintenance treatments. Randomization took place when clinically appropriate, and comedication was allowed within the first six months after randomization. The patients were enrolled from March 2001 to December 2005, and observations were censored December 2006, allowing a subgroup of patients to be followed for more than five years. The primary outcome measure was time to predefined endpoints indicating insufficient maintenance treatment, and the major secondary outcome measure was time to any study endpoint. Data were analyzed primarily by Cox proportional regression models. Results:, For the primary outcome measure, the crude Hazard Rate Ratio (HRR) (lamotrigine relative to lithium) was 0.92 [95% confidence interval (CI): 0.60,1.40]. When the primary endpoints were broken down by polarity, the HRRs (lamotrigine relative to lithium) for mania and depression were, respectively, 1.91 (95% CI: 0.73,5.04) and 0.69 (95% CI: 0.41,1.22). There was no between-group difference in terms of staying in study [HRR: 0.85 (95% CI: 0.61,1.19)]. Most treatment failures occurred within the first 1.5 years of treatment, and, among patients followed for at least five years, practically no patients were maintained successfully on monotherapy with either of the drugs. The lithium-treated patients reported diarrhea, tremor, polyuria, and thirst more frequently. Two cases, probably lamotrigine-related, of benign rash occurred. Conclusions:, No differences in maintenance effectiveness between lithium and lamotrigine could be demonstrated. Lamotrigine was better tolerated than lithium, but apparently this did not influence the outcome. [source] Expression, purification, crystallization and preliminary X-ray crystallographic studies of a novel acetylcitrulline deacetylase from Xanthomonas campestrisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2005Dashuang Shi A novel N -acetyl- l -citrulline deacetylase that is able to catalyze the hydrolysis of N -acetyl- l -citrulline to acetate and citrulline was identified from Xanthomonas campestris. The protein was overexpressed, purified and crystallized. The crystals belong to the monoclinic space group C2 and diffract to 1.75,Å resolution, with unit-cell parameters a = 94.13, b = 95.23, c = 43.61,Å, , = 93.76°. Since attempts to use homologous structural models to solve the structure via molecular replacement were unsuccessful, the selenomethionine-substituted protein was prepared using an overnight auto-induction overexpression system. Selenomethionine incorporation into the protein was verified by MALDI,TOF/TOF mass-spectroscopic analysis after trypsin digestion. The crystals of the selenomethionine-substituted protein were prepared using crystallization conditions similar to those for the native protein. Multiple anomalous dispersion (MAD) data were collected at Brookhaven National Laboratory. Structure determination is under way using the MAD phasing method. [source] | |||||||||||||||||||